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I have a 2004 330CCI.

Over the weekend, when I tried to close the top, it got about 90% completed and then it just froze. The latches were about 2" above the frame. I tried to reopen and then reclose, but neither the open or close button would do anything.

I used the allen wrench to secure the top so that I could drive the car. Any thoughts on a diagnosis?

Thank you!
 

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I am going to guess that the problem is due to frayed / fatigued wires. There is a wiring loom built into the top; it runs along the driver's side and the wires get stretched, twisted, and eventually fail due to the folding and unfolding of the top over the years. There is a good You Tube video on how to fix it, you'd have to search unless someone else has the link to the DIY video handy.
 

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I have never seen these wiring issues for myself but there are lots of pics around the forums where various harness sleeves appear to show no signs of wear on the outside... but once you get the wires out you can see that they are clearly damaged (especially check the boot/trunk wiring harness pics) - though some of these pictures look suspiciously like the wires could have been damaged by cutting into the sleeve?!
The sleeve on the harness in that video above doesn't look to be in bad shape either.

So I guess you just wait and see where the roof stops next and then examine the harness for which areas appear to be most flexed/stressed/stretched at that point?

Thanks for raising the question anyway - this was something I had not previously been aware of and I am now ready for when this happens to me!!
 

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Kostspieliger Spaß Quandt
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Thank you both for the responses. I watched the video and came home from work ready and hoping to find some frayed wires. Before I started I tried to put the top down automatically and I was amazed that it worked!

Then I held my breath and tried to close the roof, and that worked too!

So I'm temporarily relieved that the top is working, but still knowing there's a problem in there some place.

Any thoughts on other things to review or test ?

For what it's worth I saw no signs of wear and tear on the wiring harness
Check the trunk wiring harness. Affectionately known as the "elephant trunk" - it carries a number of ground and positive wires from the body into the trunk. It is a notorious weak point as the wires get frayed inside the plastic insulation and strands break, eventually the wires snap in two. Causes all kinds of intermittent trunk electrical issues. It is not unique to the convertible - it affects many BMW vehicles including e90, e46 and e39 - it does however cause a unique issue for the e46 vert opening and closing.

I owned an e46 vert for 15 years and had to repair this loom twice in that time. First time the exact same thing caught my attention - top failed to latch half way up. The issue became intermittent. Why? The trunk lid has to report "closed" for the roof to operate. The circuit for the trunk closed runs through this loom. The vibration of the roof closing or opening or the extent of the frayed wires intermittently reports the trunk "open". If the CVT is notified the trunk is open it stops opening or closing the roof.

Unfortunately most of the really good images from a decade ago are gone now thanks to Photobucket



http://forum.e46fanatics.com/showthread.php?t=664980

You do not need to cut the rubber elephant trunk to repair - you do need to remove the trunk lid carpet and disconnect the wires in the trunk lid to give some more slack. Pull the elephant trunk out at both ends, pull on the disconnected wires to get some slack and splice in new wires on the slack. For my last repair (I've done this on 4 vehicles) I cut on either side of the elephant trunk (about 16" splices) so the soldered connections were not in the elephant trunk as it barely has enough width for the existing wires and you don't want the flexing on the solder joints.

Lastly - use high grade replacement wires - I have BMW wire harnesses from stripped down cars so I match up the colours and gauge. If you use a cheap wire it will only fail faster. - Leave slack in the elephant trunk so the wires can move as it flexes. too rigid and they will break easier.
 
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